Top dressing coco

Currently have coco perlite ewc mix that gets bottle nutes with recharge and teas. Will top dressing kelp meal in flower for a terp boost work?

I don't know about "for terps" but Kelp is known to be good in general for multiple reasons, but if you're running bottled nutes you might want to use a liquid kelp product as you may not get the full benefits otherwise without soil biology breaking things down.

or steep the kelp meal, make your tea with it.